/in/foo.cc: In function 'int main()':
/in/foo.cc:29:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i<v.size()-1)
        ~^~~~~~~~~~~
/in/foo.cc:60:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i=0;i<v.size();i++)
          ~^~~~~~~~~